Light up and live! If you're commuting, we recommend you set yourself up with some reflective clothing. This is because car lights are much brighter than yours, so you might as well make use of them. Reflective clothing should be brightly coloured also. Bright colours are good during the day, reflective material is good at night, but both are needed at dawn and dusk, the most dangerous time to be on the road in terms of visibility.
Speaking of colours and visibility, flouro colours are good (we all know that), white is good (but not great in mist), yellow is good, but beware - red is difficult to see, despite being a vibrant colour. At night, red is harder to see than black, and better only than grey.